This article was published in Marketing Letters, 13 (3), 219-230, 2002.

We consider influences on market structure, arguing that market strucure should explain the extent to which any given set of market offerings are substitutes or complements. We describe recent additions to the market structure analysis literature and identify promising directions for new research in market structure analysis. Impressive advances in data collection, statistical methodology and information technology provide unique opportunities for researchers to build market structure tools that can assist “realtime” marketing decision-making.